Police say a car sped through a stop sign and hit another car making a turn. The driver of the speeding car hit a brick building and then fled the scene on foot.

Witnesses said the suspect's car caught fire after the crash.

"I don't think he had like a shirt on or anything but he seemed to just get out of the car and just take off running as fast as he could, obviously trying to get away," witness Tyrone Dobbie said.

The 25-year-old woman driving the car that was hit was injured with non-life-threatening injuries, police said. Her 26-year-old husband was killed. Their 1-year-old son is currently in serious condition at the Children's Hospital of Wisconsin.

Police said the child was strapped in a car seat.

"We got here and all we heard was the mother screaming to save her baby and we saw the fire coming from one of the vehicles and after that it was just kind of crazy," witness Terry Greer said.

Anyone with information is asked to call Milwaukee Police at 414-935-7251.